The invention relates to an electromagnetic relay with the following features:
a coil body forms a coil tube with two flanges and carries a winding on the coil tube; PA1 a first of the two flanges forms a switch space with a base side parallel to the coil axis; PA1 within the coil tube there is arranged an axial core which forms a pole face toward the switch space and is connected to an L-shaped yoke in the region of the second flange; PA1 with its free end, the yoke forms, in the region of the switch space, a bearing edge, perpendicular to the base side, for a plate-shaped armature which forms a working air gap with the pole face of the core; PA1 at least one, fixed contact support carrying a first fixed contact is secured in the coil body in the vicinity of the moving end of the armature and PA1 a contact spring formed from flat strip material is connected to the armature, carries a moving contact at one free end in the region of the moving end of the armature and is connected to a contact spring connecting pin of the relay via a connecting portion.
A relay constructed in this way is known, for example, from U.S. Pat. No. 4,596,972. The contact spring there surrounds the armature mounting in the form of an arc and is fastened to the yoke by its connecting portion, the yoke in turn forming a downwardly shaped connecting pin. With a relay of this type, in which the load current is guided via the yoke, the current path in the relay to the connection is relatively long; the ferromagnetic yoke material also has limited conductivity. This is undesirable for the switching capacity of high currents if the connecting pin with its relatively small cross-section is also produced from the same material. A connecting pin shaped on the yoke also necessitates additional expenditure, if the relay housing is to be sealed.
In the case of similarly constructed relays which are designed for high load currents, it is known to guide the load current from a connecting pin fastened in a base via a flexible copper wire directly to the contact spring and to the contact piece fastened thereon (DE 34 28 595 C2). In this way, the yoke does not have to carry the load current. However, the use of the flexible wire necessitates additional expenditure for material and assembly.
With this known relay, the fixed contact supports and optionally also the contact spring connecting pin are produced as respective punched parts and are assembled by plugging them into preshaped ducts and apertures in the coil body or a base and then fixed by a notching process or inherent pressing. This design has the drawback that the parts do not fit in the plastic part in an interlocking manner for reasons of tolerance or that particles are abraded during assembly owing to overlapping of parts. These particles can subsequently lead to problems in the relay, for example on the contacts, in the armature bearing or in the working air gap. High expenditure then has to be incurred during production, to eliminate the resultant particles by blowing or extraction devices.
It is known with other relays to punch individual parts such as contact supports from sheet metal and to extrusion-coat them either individually or linked in strips in a mould. This method of production has the drawback that the parts have to be inserted into the injection mould; strip production also entails high consumption of material. High expenditure is required in both cases for adapting the injection mould to the punching tools, in order to allow the mould to be sealed well in the region of the punching burrs.